Hertfordshire
Wraparound extensions in Hertfordshire
An L-shaped extension that fills the side return and runs across the back. Across Hertfordshire we handle the whole rear extension: survey, drawings, the planning route, building control and the build. Towns we cover here include Watford, Hemel Hempstead and Stevenage.
Wraparound projects around Watford often involve two neighbours, so we start the party wall conversations early. Post-war semis and newer estates are typical of Hertfordshire, and many have room for a full-width extension. Shrinkable clay is common in the East of England, so foundations near trees and hedges are designed to NHBC-style depth guidance.
How much does a wraparound extension cost in Hertfordshire?
For Hertfordshire we work from the East of England rate: £2,330–£3,820 per square metre of new floor, including VAT, standard specification. East of England prices run slightly above our West Midlands baseline; clay soils near trees are the main foundation variable.
| Size | Guide price inc VAT |
|---|---|
| L-shaped, about 22 m² of new floor | £51,500–£84,000 |
| L-shaped, about 30 m² of new floor | £70,000–£114,500 |
We put a fixed price in writing once the design is agreed, and explain any provisional sums such as foundations.
Do you need planning permission in Hertfordshire?
Side return infills and the side leg of a wraparound are treated as side extensions in England: single-storey, no more than 4 metres high and no wider than half the original house. They are not permitted development in conservation areas, National Parks or National Landscapes, and a joined wraparound often needs a planning application because the side and rear rules apply together.
The Party Wall etc. Act 1996 applies in England: you serve notice two months before work to a shared wall, and one month before digging foundations within 3 metres (or 6 metres for deeper foundations) of a neighbour's building. Neighbours can agree in writing; if they dissent, surveyors agree an award.
Conservation areas, National Parks, National Landscapes and the Broads restrict permitted development, and listed buildings always need listed building consent.
Where in Hertfordshire do we work?
- Watford
- Hemel Hempstead
- Stevenage
- St Albans
- Welwyn Garden City
- Cheshunt
- Hatfield
- Bishops Stortford
- Borehamwood
- Hitchin
- Hoddesdon
- Letchworth Garden City
- North Watford
- Harpenden
- Bushey
- Hertford
- Rickmansworth
- Potters Bar
- Berkhamsted
- Ware
- Enfield Lock
- Royston
- Croxley Green
- Broxbourne
- West Watford
- Batchworth
- Tring
- Chorleywood
- Codicote
- Baldock
- Abbots Langley
- Waltham Cross
FAQ
Questions people ask
Does a wraparound need planning permission?
Often yes, because the side and rear parts are judged together. Some fit within permitted development; we check before drawing.
How long does a wraparound take?
Usually 14 to 20 weeks on site, longer than a plain rear extension because of the steelwork.
Can the corner be all glass?
Yes, with a steel or aluminium post or a structural glass corner. It needs careful thermal detailing to meet Building Regulations.
Do you cover all of Hertfordshire?
We cover 32 towns and districts in Hertfordshire, including Watford, Hemel Hempstead and Stevenage.
Who builds the extension?
Vetted building teams working under contract to us; your contract is with S&K Property Investments and Improvement Ltd.